Use a canvas strategy

The large area of a typical computer interface allows you to present an
application with a mix of content and UI components. The same application that is created for the
BlackBerry PlayBook tablet
requires a different strategy. In most situations, your application should make use of the entire
screen, use gestures to control workflow, and access additional options only when necessary.

If you have a large amount of information to present, try to think of the screen as a frame that contains a small view of a large canvas. Users can move the view by dragging a finger in any direction, or by swiping to move the view quicker or a greater distance. For example, you might use this type of interaction when navigating within a map or large image.

As part of your canvas strategy, you should consider how the content behaves in
response to gestures. One way to do this is to categorize your canvas as either continuous or
discrete. A continuous canvas contains content that can be arbitrarily subdivided (for example, a
map or a building blueprint). A discrete canvas contains content that has obvious, defined
subcomponents (for example, a deck of cards, a contact list, or an eBook).

On a continuous canvas, consider allowing users to move (pan) slowly through the content, move
quickly, zoom in and out, and perhaps rotate. On a discrete canvas, you should also consider
allowing users to move (shift) slowly or quickly through the content, but there are likely some
other actions that you might want to enable using gestures. For example, you can flip over a
card, navigate within a contact list, or jump to the next chapter in a document.